Received: 7 November 2017
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Revised: 8 April 2018
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Accepted: 16 April 2018
DOI: 10.1002/mrm.27350
Magnetic Resonance in Medicine
FULL PAPER
Changes in the specific absorption rate (SAR) of radiofrequency energy in patients with retained cardiac leads during MRI at 1.5T and 3T Laleh Golestanirad1,2 | Amir Ali Rahsepar2 | John E Kirsch1 | Kenichiro Suwa2 | Jeremy C. Collins2
| Leonardo M. Angelone3 | Boris Keil4 | Rod S. Passman5 |
Giorgio Bonmassar1 | Peter Serano3 | Peter Krenz6 | Jim DeLap6 | James C. Carr2 | Lawrence L. Wald1 1 Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 2
Department of Radiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
3
Division of Biomedical Physics, Office of Science and Engineering Laboratories, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 4
Department of Life Science Engineering, Institute of Medical Physics and Radiation Protection, Giessen, Germany
5
Division of Cardiology, Department of Medicine, Northwestern University, Feinberg School of Medicine, Chicago, Illinois
6
ANSYS Inc., Canonsburg, Pennsylvania
Correspondence Laleh Golestani Rad, AA Martinos Center, Massachusetts General Hospital, Harvard Medical School, Building 75, Third Ave, Charlestown, MA 02129 Email:
[email protected] or Department of Radiology, Feinberg School of Medicine, 737 N Michigan Ave. Suite 1600, Chicago IL 60611. Email:
[email protected] Funding information National Institutes of Health, Grant/ Award Numbers: K99EB021320, R01EB00684, R01MH111875, and R03 EB024705
Purpose: To evaluate the local specific absorption rate (SAR) and heating around retained cardiac leads during MRI at 64 MHz (1.5T) and 127 MHz (3T) as a function of RF coil type and imaging landmark. Methods: Numerical models of retained cardiac leads were built from CT and X-ray images of 6 patients with retained cardiac leads. Electromagnetic simulations and bioheat modeling were performed with MRI RF body and head coils tuned to 64 MHz and 127 MHz and positioned at 9 different imaging landmarks covering an area from the head to the lower limbs. Results: For all patients and at both 1.5T and 3T, local transmit head coils produced negligible temperature rise (DT
